By John McDevitt

PHILADELPHIA (CBS) – It’s a sweet way to know if the stork is bringing a boy or a girl. Gender reveal cakes are becoming very popular.

Pastry Artist Zoe Lukas, owner of Whipped Bakeshop in Fishtown says, “I noticed it come up as a trend in the last year or so.”

She says the cakes are decorated on the outside in a way that doesn’t spoil the surprise. It might be the shape of a toy block with a teddy bear on top.

Then, once it’s cut the secret is out, “and then the icing inside of our layer cakes will have either pink or blue icing to reveal the sex of the baby that you are soon to have. So, I’m looking forward to when we get a twin cake — when somebody is having a boy and a girl — so we can do a purple filling with the colors mixed.”

Gender reveal cup cakes are also available.

To see more examples of the cakes, click here.